ABSTRACT
Fiber reinforced composite [FRC] inlay bridges have become popular for being conservative, simple and relatively inexpensive. The aim of this in vitro study was to determine the survival rate of FRC inlay bridges replacing missing maxillary lateral incisors, after being subjected to a cyclic mechanical load of 2 million cycles with a force of 30 N at a frequency of 2 Hz. In this experimental study, 30 anterior bovine teeth were used as abutments to make 15 anterior FRC inlay bridges. Fifteen acrylic resin blocks were fabricated utilizing a dentoform. The teeth were mounted in the resin blocks while trying to simulate normal tooth angulations, PDL and biologic width. Pontics were made indirectly and bridges were directly fabricated in 2x2x2 mm prepared cavities using Nulite F fiber- reinforced composite resin and polyethylene fiber based braids [NSI, Australia]. The specimens were thermocycled for 2000 cycles between 5°C and 55°C and were then exposed to two million load cycles [30 N, 2 Hz] at 130°C to the long axis of the pontics [3mm under the incisal edge] in a cyclic loading machine. Three specimens were excluded due to experimental mishandling. All 12 remaining bridges [%100] survived the applied loads. Based on the results of this study, it may be concluded that FRC bridges can tolerate more than 2 million normal masticatory forces which is equivalent to 7-9 years of clinical service
ABSTRACT
The use of Carisolv[TM] decreases unnecessary removal of sound dental tissue and reduces the possibility of pulpal exposure. However, it is expensive and time-consuming and its efficacy has not been clearly " defined. The aim of this study was to compare the efficacy, safety and efficiency of removing deep caries using conventional mechanical methods alone and in conjunction with Carisolv. This investigation was a single-blind randomized clinical trial. Forty individuals, each with a deep carious tooth [0.5-1 mm from the pulp] without signs and symptoms of necrosis or irreversible pulpitis were selected and randomly divided into two study-groups: A, all caries were mechanically removed using rotary instruments and B, Carisolv was applied on deep carious lesions and the rest of the caries were mechanically eliminated. All cavities were evaluated by a dental probe. After complete caries removal the teeth were filled as usual. The outcome variables were complete caries removal, pulpal exposure and time taken to remove caries. The results were analyzed by X[2] and Mann-Whitney tests. Three pulpal exposures occurred in group A and one in group B without a statistically significant difference. Regarding complete caries removal, the two methods were similar. The mean caries-removal time was 16 +/- 6.8 min in group A and 25.2 +/- 6.3 min in group B [P<0.001]. The amount of Carislov used for each tooth was 0.17 cc. Application of the mechanical and chemomechanical methods simultaneously, is more time-consuming and does not seem to significantly improve the treatment results
Subject(s)
Humans , Leucine/analogs & derivatives , Lysine/analogs & derivatives , Glutamic Acid/analogs & derivatives , Treatment Outcome , Clinical Trials as TopicABSTRACT
Homocysteine is an amino acid with a free thiol [Sulphydryl] group and is an intermediate formed during the metabolism of methionine to cysteine. Measurement of total plasma Homocysteine may be of value in several clinical conditions including homocysteinuria, atherosclerosis, thrombophilia and folate/vitamin B12 deficiency. The purpose of this study was to measure total plasma Homocysteine using RP-HPLC with fluorescence detection method. Total plasma Homocysteine was measured with reverse-phase HPLC with fluorescence detection after reduction of Homocysteine with tris [2-carboxyetile] phosphine [TCEP] and derivatization of plasma thiols with ammonium 7-fluorobenzo-2-oxa 1,3-diazole-4-sulfonate [SBD-F]. Findings: The limit of detection for Homocysteine was 0.2 micromol/l. The within day coefficient of variation [CV] was 2.67% to 4.56% and the between day coefficient of variation was 5.43% to 8.17%. The mean recovery of Homocysteine was 93% to 103.4%. The results show that the HPLC method with fluorescence detection for measurement of total plasma Homocysteine, is sensitive [The limit of detection 0.2 micromol/l], accurate [CV between 2.67% and 8.17%] and it has acceptable recovery [93% to 103.4%]. Therefore, it is confident method especially for investigate application
ABSTRACT
Introduction: Many clinical studies have evaluated different dentin bonding agents in treatment of dentin hypersensitivity [DH]. But the use of acid is controversial and the effect of self-etch bonding agents isn't clearly defined
Objective: The aim of this study was to compare two dentin bonding systems, prompt [self-etch bonding system] and excite [with and without acid] in treatment of DH
Materials and Methods: This clinical study had a double-blind, randomized, subject design and was performed on 41 sensitive teeth with DH. We had 3 groups e1 [we used excite without acid], e[2] [excite with acid] and p [prompt]. Two stimuli [cold water 20??c and compressed air] and two methods for evaluation [[VAS [Visual Analogue Scale] and response time]] in 3 times [before treatment, immediately after treatment and two weeks after it] were used
Results: All treatments showed significant reductions in DH. In the VAS scores, no significant difference was found. But in the response time, the groups e1, P significantly showed better results than group e2.[P<0.05]
Conclusion: Treatment effects were improved in all groups with time. Use of acid before the bonding agent had a negative effect but there was no significant difference between prompt and excite [without acid etching]. It's worth nothing that the measurement of response time to stimulus compared to the VAS method is more accurate in evaluation studies of pain rate
ABSTRACT
For more than a decade, academic libraries have been wrestling with the thorny issue of managing the acquisition of electronic resources. Where are we in the continuum from paper lists to vendor-designed management systems